U.S. patent number 6,003,196 [Application Number 09/004,999] was granted by the patent office on 1999-12-21 for upright vacuum cleaner with cyclonic airflow.
This patent grant is currently assigned to Royal Appliance Mfg. Co.. Invention is credited to Brett Latimer, Paul D. Stephens, Charles J. Thur, Michael F. Wright.
United States Patent |
6,003,196 |
Wright , et al. |
December 21, 1999 |
Upright vacuum cleaner with cyclonic airflow
Abstract
An upright vacuum cleaner (A) includes an upright housing
section (B) and a nozzle section (C). A cyclonic airflow dirt and
dust separating chamber (54) is defined in said upright housing
section. A suction source (E) pulls air and entrained dirt, dust,
and other contaminants through a main suction opening (26) formed
in the underside (24) of the nozzle and into the cyclonic airflow
chamber (54). The cyclonic airflow chamber causes the suction
airstream to travel in a cyclonic path such that the entrained
contaminants are separated therefrom and deposited into a dirt
container (52) that defines the lower portion of the chamber (54).
A main filter assembly (50) includes a main filter element (H) for
filtering residual contaminants from the suction airstream between
the chamber and the suction source. The main filter element is
preferably made from high-density polyethylene porous filter media.
A final filter assembly (F) filters the suction airstream
discharged by the suction source to ensure that the air discharged
into the atmosphere is contaminant free, including those
contaminants introduced into the airstream by the suction source
itself.
Inventors: |
Wright; Michael F. (Stow,
OH), Thur; Charles J. (Broadview Heights, OH), Latimer;
Brett (Mentor, OH), Stephens; Paul D. (Cleveland,
OH) |
Assignee: |
Royal Appliance Mfg. Co.
(Cleveland, OH)
|
Family
ID: |
21713606 |
Appl.
No.: |
09/004,999 |
Filed: |
January 9, 1998 |
Current U.S.
Class: |
15/353;
15/347 |
Current CPC
Class: |
A47L
5/28 (20130101); A47L 9/165 (20130101); A47L
9/1666 (20130101); A47L 9/1683 (20130101); B01D
39/1692 (20130101); B01D 45/16 (20130101); B01D
46/10 (20130101); B01D 46/2411 (20130101); B01D
46/521 (20130101); B01D 50/002 (20130101); B04C
5/13 (20130101); B04C 9/00 (20130101); A47L
9/127 (20130101); Y10S 55/03 (20130101); B01D
2279/55 (20130101); B04C 2009/004 (20130101) |
Current International
Class: |
A47L
5/28 (20060101); A47L 9/16 (20060101); A47L
9/10 (20060101); A47L 5/22 (20060101); A47L
9/12 (20060101); B01D 39/16 (20060101); B01D
50/00 (20060101); B04C 9/00 (20060101); A47L
009/10 () |
Field of
Search: |
;15/353,352,347
;55/337,523,528,379,DIG.2,DIG.3 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
1049292 |
|
Nov 1966 |
|
GB |
|
2265096A |
|
Sep 1993 |
|
GB |
|
2 280 388A |
|
Feb 1995 |
|
GB |
|
WO 84 02282 |
|
Jun 1984 |
|
WO |
|
Primary Examiner: Warden, Sr.; Robert J.
Assistant Examiner: Aldag; Andrew
Attorney, Agent or Firm: Fay, Sharpe, Fagan, Minnich &
McKee, LLP
Claims
Having thus described the preferred embodiments, the invention is
now claimed to be:
1. A vacuum cleaner comprising:
a housing defining a cyclonic airflow chamber for separating
contaminants from a suction airstream, said housing further
comprising a suction airstream inlet and a suction airstream outlet
in fluid communication with said cyclonic airflow chamber;
a nozzle base including a main suction opening, said main suction
opening being fluidically connected with said cyclonic airflow
chamber inlet;
an airstream suction source having an inlet fluidically connected
to said cyclonic airflow chamber outlet and a suction source
exhaust outlet, said suction source selectively establishing and
maintaining a suction airstream from said nozzle main suction
opening to said suction source exhaust outlet;
a main filter assembly positioned centrally within said cyclonic
airflow chamber for filtering residual contaminants from said
suction airstream prior to exit of said suction airstream from said
cyclonic airflow chamber, said main filter assembly comprising a
washable, rigid filter element including high-density polyethylene
open-celled foam porous filter media.
2. A vacuum cleaner comprising:
a housing defining a cyclonic airflow chamber for separating
contaminants from a suction airstream, said housing further
comprising a suction airstream inlet and a suction airstream outlet
in fluid communication with said cyclonic airflow chamber;
a nozzle base including a main suction opening, said main suction
opening being fluidically connected with said cyclonic airflow
chamber inlet;
an airstream suction source having an inlet fluidically connected
to said cyclonic airflow chamber outlet and a suction source
exhaust outlet, said suction source selectively establishing and
maintaining a suction airstream from said nozzle main suction
opening to said suction source exhaust outlet;
a main filter assembly positioned in fluid communication between
said cyclonic airflow chamber and said suction source for filtering
residual contaminants from said suction airstream downstream
relative to said cyclonic airflow chamber, said main filter
assembly comprising a filter element including high-density
polyethylene porous filter media with pores having an average pore
size of approximately 45 .mu.m to approximately 90 .mu.m.
3. The vacuum cleaner as set forth in claim 2 wherein said filter
element is one of cylindrical and frusto-conical in overall shape
and has a convoluted outer surface defining at least two concentric
sections separated by a generally annular passage.
4. The vacuum cleaner as set forth in claim 2 wherein said main
filter assembly further comprises:
an upper portion including an aperture defined therethrough in
fluid communication with said suction airstream outlet of said
cyclonic chamber; and,
a lower portion housing said filter element, said lower portion
including a plurality of airflow apertures formed therethrough,
said upper and lower portions of said main filter assembly
including cooperating fasteners for releasably connecting said
lower portion to said upper portion, wherein said filter element is
positioned between said upper portion and said lower portion
plurality of airflow apertures to filter said suction airstream
exiting said cyclonic airflow chamber and flowing through said
suction airstream outlet.
5. The vacuum cleaner as set forth in claim 4 wherein said
cooperating fasteners comprise a first set of tangs extending from
said upper portion of said main filter assembly, and a second set
of mating tangs provided on said lower portion of said main filter
assembly.
6. The vacuum cleaner as set forth in claim 2 further comprising a
final filter assembly positioned on one of said housing and said
nozzle base, said final filter assembly being in fluid
communication with said suction source exhaust outlet for filtering
said suction airstream exhausted from said suction source exhaust
outlet and for discharging said suction airstream into the
atmosphere.
7. The vacuum cleaner as set forth in claim 6 wherein said final
filter assembly comprises a high efficiency particulate arrest
(HEPA) filter media.
8. A vacuum cleaner comprising:
a housing defining a cyclonic airflow chamber for separating
contaminants from a suction airstream, said housing further
comprising a suction airstream inlet and a suction airstream outlet
in fluid communication with said cyclonic airflow chamber, wherein
a lower portion of said cyclonic airflow chamber is defined by a
dirt container for receiving and retaining dirt and dust separated
from said suction airstream, said container being pivotable between
an operative position and an open position, and including an open
upper end defined by an inclined edge such that when said dirt
container is pivoted fully into the open position, the inclined
edge is located in a substantially horizontal plane to inhibit
spillage of the separated dirt and dust;
a nozzle base including a main suction opening, said main suction
opening being fluidically connected with said cyclonic airflow
chamber inlet;
an airstream suction source having an inlet fluidically connected
to said cyclonic airflow chamber outlet and a suction source
exhaust outlet, said suction source selectively establishing and
maintaining a suction airstream from said nozzle main suction
opening to said suction source exhaust outlet;
a main filter assembly positioned in fluid communication between
said cyclonic airflow chamber and said suction source for filtering
residual contaminants from said suction airstream downstream
relative to said cyclonic airflow chamber, said main filter
assembly comprising a filter element including high-density
polyethylene porous filter media.
9. An upright vacuum cleaner comprising:
an upright housing section including a handle;
a nozzle base section hingedly interconnected with the upright
housing section, said nozzle base section including a main suction
opening formed in an underside thereof;
a cyclonic airflow chamber defined in said upright housing section
for separating dust and dirt from a suction airstream;
a suction source located in one of said upright housing section and
said nozzle base section and having a suction airflow inlet in
fluid communication with said cyclonic chamber and a suction
airflow outlet;
a main filter assembly located in said cyclonic chamber and
including a rigid filter element for filtering residual dust and
dirt from a suction airstream as said suction airstream exits said
cyclonic airflow dust and dirt separating chamber, said filter
element comprising rigid, porous high-density polyethylene filter
media; and
a final filter assembly located on one of said housing and said
nozzle base, said final filter assembly being connected in fluid
communication with said suction airflow outlet of said suction
source for filtering said suction airstream exhausted by said
suction source prior to said suction airstream being dispersed into
the atmosphere.
10. The upright vacuum cleaner as set forth in claim 9 wherein said
final filter assembly comprises a high efficiency particulate
arrest (HEPA) filter media.
11. The upright vacuum cleaner as set forth in claim 9 wherein said
porous filter media has pores with an average pore size of less
than approximately 90 .mu.m.
12. An upright vacuum cleaner comprising:
an upright housing section including a handle;
a nozzle base section hingedly interconnected with the upright
housing section, said nozzle base section including a main suction
opening formed in an underside thereof;
a cyclonic airflow chamber defined in said upright housing section
for separating dust and dirt from a suction airstream;
a suction source located in one of said upright housing section and
said nozzle base section and having a suction airflow inlet in
fluid communication with said cyclonic chamber and a suction
airflow outlet;
a main filter assembly located between said cyclonic chamber and
said suction source for filtering residual dust and dirt from a
suction airstream after said suction airstream passes through said
cyclonic airflow dust and dirt separating chamber, said main filter
assembly including a porous high-density polyethylene foam main
filter element having a convoluted outer surface that defines at
least a first elongated inner filter section and a second elongated
filter section, wherein said first and second filter sections are
separated by a deep airflow passage; and,
a final filter assembly located on one of said housing and said
nozzle base, said final filter assembly being connected in fluid
communication with said suction airflow outlet of said suction
source for filtering said suction airstream exhausted by said
suction source prior to said suction airstream being dispersed into
the atmosphere.
13. The upright vacuum cleaner as set forth in claim 12 wherein a
lower portion of said cyclonic airflow chamber is defined by a dirt
container for receiving and retaining dirt and dust separated from
said suction airstream, said container being pivotable between an
operative position and an open position and including an open upper
end defined by an inclined edge such that when said dirt container
is pivoted fully into the open position, the inclined edge is
located in a substantially horizontal plane to inhibit spillage of
the separated dirt and dust.
14. A vacuum cleaner comprising:
a nozzle section;
a housing section connected to said nozzle section and in fluid
communication with said nozzle section;
a cyclonic airflow chamber located in said housing section for
separating dirt and dust from a suction airstream flowing into said
housing section between an inlet located at a periphery of said
housing section and an outlet located at an apex of said housing
section;
a filter chamber located in said housing section between said
cyclonic airflow chamber and said outlet of said housing section,
said filter chamber comprising:
a first filter housing, and
a first filter element mounted in said first filter housing,
wherein said first filter element and said first filter housing
cooperate to define a tortuous flow path for air flowing from said
cyclonic airflow chamber to said outlet of said housing section,
said first filter element defining at least a first elongated inner
filter section and a second elongated filter section, wherein said
first and second filter sections are separated by an annular
airflow passage.
15. The vacuum cleaner as set forth in claim 14 wherein said first
filter element comprises high density polyethylene porous filter
media having an average pore size of approximately 45 .mu.m to
approximately 90 .mu.m.
16. A vacuum cleaner comprising:
a nozzle section;
a housing section connected to said nozzle section and in fluid
communication with said nozzle section, said housing section
further comprising a dirt container for receiving and retaining
dirt and dust separated from said suction airstream, said container
being pivotable between an operative position and an open position
and including an open upper end defined by an inclined edge such
that when said dirt container is pivoted fully into the open
position, the inclined edge is located in a substantially
horizontal plane to inhibit spillage of the separated dirt and
dust;
a cyclonic airflow chamber located in said housing section for
separating dirt and dust from a suction airstream flowing into said
housing section between an inlet located at a periphery of said
housing section and an outlet located at an apex of said housing
section;
a filter chamber located in said housing section between said
cyclonic airflow chamber and said outlet of said housing section,
said filter chamber comprising:
a first filter housing, and
a first filter element mounted in said first filter housing,
wherein said first filter element and said first filter housing
cooperate to define a tortuous flow path for air flowing from said
cyclonic airflow chamber to said outlet of said housing
section.
17. The vacuum cleaner as set forth in claim 16 further
comprising:
a main suction opening located in said nozzle section and connected
to a suction airstream inlet of said cyclonic chamber; and,
a suction source connected to said outlet of said housing section
for suctioning an airstream from said nozzle main suction opening
into and through said cyclonic chamber to an exhaust outlet of said
suction source.
18. The vacuum cleaner as set forth in claim 17 further comprising
a second filter chamber connected to said exhaust outlet of said
suction source and a second filter element for filtering
contaminants from said airstream exhausted by said suction
source.
19. The vacuum cleaner as set forth in claim 18 wherein said second
filter element comprises high efficiency particulate arrest filter
media.
20. The vacuum cleaner as set forth in claim 18 wherein said first
filter element includes a convoluted outer surface.
Description
BACKGROUND OF THE INVENTION
The present invention relates to vacuum cleaners. More
particularly, the present invention relates to upright vacuum
cleaners used for suctioning dirt and debris from carpets and
floors.
Upright vacuum cleaners are ubiquitous. They are known to include
an upper portion having a handle, by which an operator of the
vacuum cleaner may grasp and maneuver the cleaner, and a lower
cleaning nozzle portion which travels across a floor, carpet, or
other surface being cleaned. The upper portion is often formed as a
rigid plastic housing which encloses a dirt and dust collecting
filter bag, although the upper portion may simply be an elongated
handle with the filter bag, and an external cloth bag, being hung
therefrom. The cleaning nozzle is hingedly connected to the upper
handle portion such that the upper portion is pivotable between a
generally vertical upright storage position and an inclined
operative position. The underside of the nozzle includes a suction
opening formed therein which is in fluid communication with the
filter bag.
A vacuum or suction source such as a motor and fan assembly is
enclosed either within the nozzle portion or the upper portion of
the cleaner. The vacuum source generates the suction required to
pull dirt from the carpet or floor being vacuumed through the
suction opening and into the filter bag. A rotating brush assembly
is typically provided in proximity with the suction opening to
loosen dirt and debris from the surface being vacuumed.
To avoid the need for vacuum filter bags, and the associated
expense and inconvenience of replacing the bag, another type of
upright vacuum cleaner utilizes cyclonic airflow, rather than a
filter bag, to separate a majority of the dirt and other
particulates from the suction airstream. The air is then filtered
to remove residual particulates, returned to the motor, and
exhausted.
Such prior cyclonic airflow upright vacuum cleaners have not been
found to be entirely effective and convenient to use. For example,
with these prior cyclonic airflow vacuum cleaners, the process of
emptying dust and dirt from the cyclonic chamber dirt collection
container has been found to be inconvenient, and often resulted in
the spillage of the cup contents. Likewise, with these prior units,
replacement of the filter element has not been convenient. Other
cyclonic airflow vacuum cleaners have been found to exhaust air
which is not free of residual contaminants. For example, one prior
unit filters the airstream after it passes through the cyclonic
chamber, but thereafter passes the airstream through the motor
assembly where it is potentially recontaminated by the motor
assembly, itself, prior to its being exhausted into the
atmosphere.
Because the cyclonic action of such vacuum cleaners does not
completely remove all dust, dirt, and other contaminants from the
suction airstream, it is necessary to include a filter downstream
from the cyclonic chamber. As such, prior cyclonic airflow vacuum
cleaners have heretofore included conventional filter elements
including conventional media to filter the airstream after it
passes through the cyclonic chamber. These prior filter elements
have caused considerable difficulties. A conventional filter that
is sufficiently fine to filter the airstream effectively unduly
restricts airflow and decreases the effectiveness of the cyclonic
action. On the other hand, a coarse filter does not effectively
filter the airstream of residual contaminants. Further,
conventional filter media, such as paper or fibrous media, has been
found to clog readily, thereby unduly decreasing airflow rates over
time. Thus, a need has been found for a cyclonic airflow vacuum
cleaner with an effective filter positioned downstream relative to
the cyclonic chamber for effectively filtering the airstream
without clogging.
Accordingly, it has been deemed desirable to develop a new and
improved upright vacuum cleaner which would overcome the foregoing
difficulties and others while providing better and more
advantageous overall results.
SUMMARY OF THE INVENTION
According to the present invention, a new and improved upright
vacuum cleaner is provided.
In accordance with a first aspect of the invention, an upright
vacuum cleaner includes a housing defining a cyclonic airflow
chamber for separating contaminants from a suction airstream. The
housing includes a suction airstream inlet and a suction airstream
outlet in fluid communication with the cyclonic airflow chamber. A
nozzle base includes a main suction opening which is fluidically
connected with said cyclonic airflow chamber inlet. An airstream
suction source is provided and has an inlet fluidically connected
to said cyclonic airflow chamber outlet and a suction source
exhaust outlet. The suction source selectively establishes and
maintains a suction airstream from the nozzle main suction opening
to the suction source exhaust outlet. A main filter assembly is
positioned in fluid communication between the cyclonic airflow
chamber and the suction source for filtering residual contaminants
from the suction airstream downstream relative to the cyclonic
airflow chamber. The main filter assembly comprises a filter
element including high-density polyethylene porous filter
media.
In accordance with another aspect of the invention, a vacuum
cleaner includes an upright housing section including a handle. A
nozzle base section is hingedly interconnected with the upright
housing section and includes a main suction opening formed in an
underside thereof. A cyclonic airflow chamber is defined in the
upright housing section and separates dust and dirt from a suction
airstream. A suction source is located in the upright section or
the nozzle section and has a suction airflow inlet in fluid
communication with the cyclonic chamber and a suction airflow
outlet. A main filter assembly is located between the cyclonic
chamber and the suction source for filtering residual dust and dirt
from the suction airstream after the suction airstream passes
through the cyclonic airflow chamber. A final filter assembly is
located on either the housing or the nozzle base and is connected
in fluid communication with the suction airflow outlet of the
suction source for filtering the suction airstream exhausted by the
suction source prior to the suction airstream being dispersed into
the atmosphere.
In accordance with a further aspect of the invention, a vacuum
cleaner includes a nozzle section. A housing section is connected
to the nozzle section and is in fluid communication with the nozzle
section. A cyclonic airflow chamber is located in the housing
section for separating dirt and dust from a suction airstream
flowing into the housing section between an inlet located at a
periphery of the housing section and an outlet located at an apex
of the housing section. A filter chamber is located in the housing
section between the cyclonic airflow chamber and the outlet of the
housing section. The filter chamber includes a first filter housing
and a first filter element mounted in the first filter housing. The
first filter element and the first filter housing cooperate to
define a tortuous flow path for air flowing from the cyclonic
airflow chamber to the outlet of the housing section.
One advantage of the present invention is the provision of a new
and improved vacuum cleaner.
Another advantage of the invention is found in the provision of a
vacuum cleaner with a cyclonic airflow chamber through which the
suction airstream flows for separating dust and dirt from the
airstream and for depositing the separated dust and dirt into an
easily and conveniently emptied dirt cup.
Still another advantage of the present invention resides in the
provision of a cyclonic airflow upright vacuum cleaner with a main
filter that effectively filters residual contaminants from the
suction airstream between the cyclonic airflow chamber and the
motor assembly without unduly restricting airflow and without
premature clogging.
Yet another advantage of the invention is the provision of a
cyclonic airflow upright vacuum cleaner with a final filter located
downstream from the suction motor assembly for filtering the
suction airstream immediately prior to its exhaustion into the
atmosphere.
A further advantage of the invention is the provision of a vacuum
cleaner with both a main filter and a final filter wherein both the
main and final filter are easily removable and replaceable.
A still further advantage of the present invention is the provision
of a vacuum cleaner with a filter element mounted in a filter
housing wherein the filter element and filter housing cooperate to
provide a tortuous flow path for air flowing therethrough.
Still other benefits and advantages of the invention will become
apparent to those skilled in the art upon reading and understanding
the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may take form in certain components and structures,
preferred embodiments of which will be illustrated in the
accompanying drawings wherein:
FIG. 1 is a perspective view illustrating a cyclonic airflow
upright vacuum cleaner in accordance with the present
invention;
FIG. 2 is a front elevational view of the vacuum cleaner
illustrated in FIG. 1;
FIGS. 3 and 4 are left and right side elevational views,
respectively, of the vacuum cleaner shown in FIG. 1;
FIG. 5 is a rear elevational view of the vacuum cleaner of FIG. 1,
further showing the required suction hose assemblies in broken
lines for clarity;
FIG. 6 is a bottom plan view of the vacuum cleaner of FIG. 1;
FIG. 7 is a front elevational view of the upright body portion of
the vacuum cleaner of FIG. 1;
FIG. 8 is a partial side view in cross-section of the vacuum
cleaner illustrated in FIG. 1, and further diagrammatically
illustrating the suction airstream flow;
FIG. 9 is a perspective view of the upright body portion shown in
FIG. 7, with the dirt cup and main filter housing removed for
clarity;
FIG. 10 is an exploded perspective view of the main filter, main
filter housing, and dirt cup;
FIG. 11 is a perspective view of the final filter assembly in
accordance with the present invention;
FIGS. 12A and 12B are rear elevational and bottom plan views,
respectively, of the upper portion of the main filter housing;
FIG. 13A is a perspective view of a main filter in accordance with
the present invention;
FIG. 13B is a bottom plan view of the main filter;
FIG. 13C is a cross-sectional view of the main filter along line
C--C of FIG. 13B;
FIG. 13D is a cross-sectional view of an alternative main filter
element in accordance with the present invention; and,
FIG. 14 is a front elevational view, partially in cross-section
along line E--E of FIG. 8, illustrating the upright body portion of
the vacuum cleaner of FIG. 1.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the FIGURES, wherein the showings are for purposes
of illustrating preferred embodiments of the invention only and not
for purposes of limiting the same, FIGS. 1-6 illustrate an upright
vacuum cleaner A including an upright housing section B and a
nozzle base section C. The sections B,C are pivotally or hingedly
connected through the use of trunnions or another suitable hinge
assembly D so that the upright housing section B pivots between a
generally vertical storage position (as shown) and an inclined
operative position. Both the upright and nozzle sections B,C are
preferably made from conventional materials such as molded plastics
and the like. The upright section B includes a handle 20 extending
upward therefrom by which an operator of the vacuum A is able to
grasp and maneuver the vacuum.
During vacuuming operations, the nozzle base C travels across the
floor, carpet, or other subjacent surface being cleaned. The
underside 24 (FIG. 6) of the nozzle includes a main suction opening
26 formed therein which extends substantially across the width of
the nozzle at the front end thereof. The main suction opening 26 is
in fluid communication with the vacuum upright body section B
through a passage 30 and a connector hose assembly 34 (FIG. 5). A
rotating brush assembly 36 is positioned in the region of the
nozzle main suction opening 26 for contacting and scrubbing the
surface being vacuumed to loosen embedded dirt and dust. A
plurality of wheels 38 support the nozzle on the surface being
cleaned and facilitate its movement thereacross.
The upright vacuum cleaner A includes a vacuum or suction source
for generating the required suction airflow for cleaning
operations. With reference particularly to FIGS. 5 and 9, a
suitable suction source, such as an electric motor and fan assembly
E, generates a suction force in a suction inlet 40 an exhaust force
in an exhaust outlet 42. The motor assembly airflow exhaust outlet
42 is in fluid communication with a final filter assembly F for
filtering the exhaust airstream of any contaminants immediately
prior to its discharge into the atmosphere. The motor assembly
suction inlet 40, on the other hand, is in fluid communication with
an elongated suction conduit 46 which extends upward from the
motor/fan assembly E to an upper region of the upright section B
where it communicates with the cyclonic suction airflow dust and
dirt separating region G of the vacuum A to generate a suction
force therein.
With reference particularly to FIGS. 7 and 8, the cyclonic suction
airflow dust and dirt separating region G housed in the upright
section B includes a main filter housing assembly 50 and a mating
dust and dirt cup or container 52. The sections 50,52 together
define a generally cylindrical cyclonic airflow chamber 54.
It may be seen with reference also to FIG. 10 that the main filter
housing assembly 50 is, itself, constructed from two mating
sections--an upper fixed housing section 50a, and a lower,
detachable filter housing section 50b. The lower detachable filter
housing section 50b receives and retains a main filter element or
cartridge H. The filter housing section 50b releasably connects
with the upper housing section 50a to secure the filter element H
in an operative filtering position. More particularly, the section
50b includes a plurality of tabs or tangs 54b extending therefrom.
Likewise, with reference also to FIG. 12B, it is shown that the
upper housing section 50a includes mating tabs or tangs 54a. Thus,
those skilled in the art will recognize that the components 50a,50b
connect in a key-like fashion upon rotation of the filter housing
section 50b in relation to the upper housing section 50a so that a
filter element H is operatively secured in position. Of course,
rather than the mating tabs 54a,54b, the two housing sections
50a,50b may alternatively include mating threads, clips, or other
suitable cooperating fastening means. The filter housing section
50b includes a plurality of apertures, slots, or other passages 56
formed therethrough, preferably in the lower half thereof, so that
the suction airstream flows freely from the chamber 54 into the
filter housing section 50b and to the main filter element H.
The housing upper section 50a includes a suction airflow outlet
passage 60 (FIG. 8) which communicates with the cyclonic chamber 54
through an aperture 62. The outlet passage 60 also communicates
with the elongated suction conduit 46 leading to the motor/fan
assembly E when the main filter housing assembly 50 is operatively
connected to the vacuum upright section B. FIGS. 8 and 9 show that
the elongated suction conduit 46 extends from the motor/fan
assembly E upward to communicate with the main filter housing
suction outlet passage 60 so that the suction inlet of the
motor/fan assembly E is able to fluidically communicate with the
cyclonic chamber 54. When the main filter housing assembly 50 is
assembled and in the operative position as described, a mouth 66
(FIG. 10) of the filter element H mates with the periphery of the
aperture 62 in a fluid-tight relationship. As such, the suction
airflow from the cyclonic chamber 54 to the motor/fan assembly
suction inlet 42 is not able to bypass the main filter element H,
but instead must pass therethrough and be filtered of residual
contaminants. It is preferable that the aperture 62, and thus the
main filter element H be centrally located in the cyclonic chamber
54 to facilitate the cyclonic airflow in the chamber.
The suction airstream enters an upper portion of the cyclonic dust
and dirt separation chamber 54 through a generally tangential
suction airstream inlet 80. In the preferred embodiment, as shown
in FIGS. 12A-12B, the cyclonic chamber airstream inlet 80 is formed
in the upper section 50a of the main filter housing assembly 50. It
is noted that the inlet 80 is disposed entirely on one side of a
center line 81 of the upper housing section so as to induce a
swirling flow around the filter housing section 50b. The suction
airstream inlet 80 of the chamber 54 is in fluid communication with
a suction airstream hose 82 through a fitting 84. As shown in FIG.
5, the hoses 82,34 are fluidically connected via fitting 86. As
such, the main suction opening 26 formed in the nozzle underside 24
is in fluid communication with the cyclonic chamber 54 through the
passage 30, the hoses 34,82, and the cyclonic chamber suction inlet
80.
The dirt container 52 of the cyclonic airflow dust and dirt
separating assembly G is constructed for large capacity and ease of
emptying the contents as necessary. In FIG. 8, it may be seen that
the dirt container 52 defines over 1/4 the volume of the cyclonic
chamber 54. As such, the capacity of the container 52 is maximized
to lengthen the operational time before the dirt container 52 must
be emptied.
The dirt container 52 is connected to the vacuum upright section B
through use of a hinge assembly 90 which allows the dirt container
52 to pivot as indicated by the arrow I between an operative
upright position and an open forwardly tilted position. As shown
herein, the hinge 90 comprises a first component 92 connected to
the dirt container 52 and a second mating component 94 formed on
the upright section B. Once the dirt container 52 is pivoted to the
open position, it may be pulled upward and away from the section B
and separated therefrom for ease of emptying the dirt container. Of
course, after the dirt container is emptied, the foregoing
procedure is reversed so that the dirt container is once again in
the operative position. A handle 96 is provided on the exterior of
the container 52 to facilitate operator movement of the container
between the operative, open, and removed position. A resiliently
biased latch 98 retains the dirt container in the operative
position. The latch 98 is biased through use of a spring or other
resilient member, or via the natural resiliency of the plastic from
which it is molded.
With continuing reference to FIG. 8, the dirt container upper edge
100 defining an open upper end of the container 52 is preferably
inclined downwardly in the direction away from the handle 96 or
front of the container 52. The main filter housing assembly section
50 is formed with a complimentary mating inclined edge 102, and a
seal such as a gasket or other structure (not shown) is provided
between the edges 100,102 to prevent air leakage into the cyclonic
airflow chamber 54. The inclined upper edge 100 of the dirt
container 52 also ensures that, when the container is pivoted to
the open position, the upper edge 100 lies in a substantially
horizontal plane. As such, the contents of the container are much
less likely to spill when the container is opened during emptying
operations. Preferably, the angle at which the upper edge 100 is
inclined from horizontal is selected, in combination with the
maximum distance the container is able to be pivoted on the arc I
when opened, such that when the container is fully opened, the
upper edge lies in a substantially horizontal plane.
As is shown in FIGS. 13A-13C, the main filter element H is
preferably generally frusto-conical in overall configuration,
converging in the direction away from the filter mouth 66 toward an
opposite filter end 110. However, those skilled in the art will
recognize that a cylindrical or other filter configuration may be
advantageously employed without departing from the scope and
overall intent of the invention.
The preferred filter media comprises Porex.RTM. brand high density
polyethylene-based open-celled porous media available commercially
from Porex Technologies Corp., Fairburn, Ga. 30213, or an
equivalent foraminous filter media. This preferred filter media is
a rigid open-celled foam that is moldable, machinable, and
otherwise workable into any shape as deemed advantageous for a
particular application. Most preferably, to optimize filtration but
also to allow sufficient airflow rates, the preferred filter media
has an average pore size in the range of 45 .mu.m to 90 .mu.m. As
is shown in FIGS. 13A-13C, the filter H is most preferably formed
in a convoluted or circuitous configuration to maximize an outer
surface area 112 of the filter. The maximized surface area 112
allows for the filter media to have a smaller pore size without
unduly restricting the airflow therethrough. Most preferably, the
filter media is formed into at least two elongated and concentric
cylinders and/or frustums 114a,114b with a deep annular passage 116
defined therebetween. Preferably, a deep central passage 118 is
defined in the innermost cylinder or frustum 114a. However, it
should be appreciated that other filter designs could also be used
if so desired. For example, it is possible to use a filter element
not having a deep central passage. FIG. 13D illustrates such an
alternative configuration of the main filter element H'. Like
components relative to the main filter element H are identified
with like numerals including a primed (') suffix. The filter
element H' is formed by concentric cylindrical portions 114a',114b'
separated by a deep annular passage 116'. However, unlike the main
filter element H, the element H' does not include a deep central
passage formed in the inner cylinder 114a'.
As mentioned, the subject vacuum A also comprises a final filter
assembly F for filtering the suction airstream downstream from the
motor/fan assembly and immediately prior to its exhaustion into the
atmosphere. The preferred final filter assembly F is illustrated
most clearly in FIG. 11 and comprises a suction airstream inlet 120
which is connected in fluid communication with the exhaust outlet
42 of the motor and fan assembly E. The inlet 120 is itself in
fluid communication with an elongated plenum 122 that opens to the
atmosphere and houses filter media. A protective grid or grate
structure is snap-fit or otherwise effectively secured over the
plenum 122 to secure the filter media in place. The filter media is
preferably a high efficiency particulate arrest (HEPA) filter
element in a sheet or block form. The filter media is retained in
position in the plenum by the grid 124, but is easily replaced by
removing the grid. As such, those skilled in the art will recognize
that even if the motor/fan assembly causes contaminants to be
introduced into the suction airstream downstream from the main
filter element H, the final filter assembly F will remove the same
such that only contaminant-free air is discharged into the
atmosphere.
Referring primarily to FIGS. 8 and 14, the operation of the vacuum
cleaning apparatus A is illustrated, with the flow of the suction
airstream indicated by use of arrows J. The motor/fan assembly E or
other suction generator establishes a suction force at its suction
inlet 42, in the elongated suction conduit 46, and thus in the
cyclonic separation chamber 54. This suction force or negative
pressure in the chamber 54 is communicated to the main suction
opening 26 formed in the nozzle underside 24 through the hoses
82,34 (FIG. 5) and associated fittings. This, then, in combination
with the scrubbing action of the rotating brush assembly 36 causes
dust and dirt from the surface being cleaned to be entrained in the
suction airflow J and pulled into the upper portion of the chamber
54 through the generally tangential inlet 80.
The location of the inlet 80, the outlet passage 60, and the
generally cylindrical configuration of the chamber 54 causes the
suction airstream to follow a swirling or cyclonic path downward
within the chamber 54 and then to move upward through a central
portion of the chamber 54 toward the centrally located main filter
housing section 50b. The orientation of the inlet 80 will affect
the direction of cyclonic airflow, and the invention is not meant
to be limited to a particular direction, i.e, clockwise or
counterclockwise. Those skilled in the art will certainly recognize
that the term "cyclonic" as used herein is not meant to be limited
to a particular direction of airflow rotation. This cyclonic action
separates a substantial portion of the entrained dust and dirt from
the suction airstream and causes the dust and dirt to be deposited
in the dirt cup or container 52. The suction airstream then passes
through the apertures 56 formed in the main filter housing section
50b, passes through the main filter element H so that residual
contaminants are removed, and exits the cyclonic chamber 54 through
the suction airstream outlet passage 60 formed in the main filter
housing section 50a. The suction airstream is communicated to the
motor/fan assembly E and exhausted through the outlet 42 (as
indicated by broken arrows) to the final filter assembly F where it
is filtered again by the HEPA filter to remove any contaminants
that passed through the chamber 54 and the filter H, and any
contaminants in the airstream due to its passage through the
motor/fan assembly E.
The main filter element H can be cleaned by washing it, either
manually or in a dishwasher--since it is dishwasher-safe--to remove
dust or dirt particles adhering to the filter element. It is,
however, important that the filter H be dried before it is used
again. The final filter media of the filter assembly F, however,
can not be cleaned and must be replaced when it becomes
clogged.
The invention has been described with reference to the preferred
embodiments. Obviously, modifications and alterations will occur to
others upon reading and understanding the preceding detailed
description. It is intended that the invention be construed as
including all such modifications and alterations insofar as they
come within the scope of the appended claims or the equivalents
thereof.
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